Satellite communications require equipment such as ground stations, low noise block down converters, transmission cables, and modulator/demodulators. The ground station receives radio frequency signals from satellites; the low noise block down converter amplifies the received radio frequency signals and converts the amplified radio frequency signals to intermediate frequency signals; and the transmission cables transmit the intermediate signals to the modulator/demodulator.
Generally, the low noise block down converter may include a radio frequency circuit and an intermediate circuit electrically connecting to the radio frequency circuit. The radio frequency circuit receives radio frequency signals, converts the radio frequency signals to intermediate signals, and transmits the intermediate signals to the intermediate circuit.
The ground station uses a highly directional receiving device, i.e., dish antenna, which has to be precisely directed toward satellites in orbit at 36,000 kilometers in altitude. For example, if a dish antenna with a 180 cm diameter shifts 2 cm horizontally, or 3 cm vertically, the signals will become weak or even disappear. In addition, if the dish antenna is configured to use electromagnetic waves in a frequency band of 26-40 GHz, an accuracy of 0.1 degree is needed, and the tolerance has to be within 0.02 degrees for aiming precisely at satellites.
This “Discussion of the Background” section is provided for background information only. The statements in this “Discussion of the Background” are not an admission that the subject matter disclosed in this “Discussion of the Background” section constitutes prior art to the present disclosure, and no part of this “Discussion of the Background” section may be used as an admission that any part of this application, including this “Discussion of the Background” section, constitutes prior art to the present disclosure.